Track magnet and circuits



Get. 5 I926.

M.'D. MINNICK TRgcK MAGNET AND CIRCUITS M I'll/innit]:

is; is as IuEi D. TO NATEANIEL raiser car es.

r414 .LCK, 0E .QMQWABK, I'll-.111 ASSEGNGE, BY MESNE ASSIGNMENTS,

LANHGN AND RALPH VJ. SHIELDS, TRUSTEES1 TRACK liIAGlFIIE'i AND CIRCUITS.

Application filed November 23, 1921, Serial No. 517,390. Renewed'June22, 1925.

r-in object or" m" invention is to communicate magnetic impulses from a.track to rollstoclr thereon in an improved manner and to cooperate witha mechanism carried by the rolling stock; for instance, such mechanismas is disclosed by the co-penoing application, automatic train controlsystem, jointly invented by h ieyer D. Minniclr, Julian Hampson, CharlesW. Burrows, and Charles Messiclr, filed November 23rd, 1921, Serial No.517,391. I

Other objects are to combine the required number of improved alternatingcurrent track magnets with circuits and relays hav ing theleast'possible departure from stand ard approved wayside signalpractice.

Man failure, which automatic train control guards against, is mostdangerous on trunk lines where tra'tfic' is densest and heavy fasttrains follow each other at short intervals, all going in the samedirection, and a typical installation of track magnets and circuits forimproved automatic train control under such conditions is described inthe detail description from which additional objects may appear.

ll hen blocks are of uniform length and no special conditions arepresent, the functions oi the track magnets in the preferredconstruction are as follows:

1. Each block is provided with two track magnets, one at the entrance,and one in the middle. These magnets are dead when the lock isunoccupied.

2. When a block is entered the magnets are energized and made alive fora predetermin'ed length of time, for instance, ninety seconds if theblock ahead is unoccupied.

3. The magnets of an occupied block are dead if the block ahead isoccugied.

Additional functions may appear from the following detail descr tion inwhich a track having a straight portion and also special conditions areshown.

Referring to the accompanying drawings:

Fig. 1 is a diagrammatic'view of atracl equipped with magnets andwiring.

Fig. 2 and 3 continuations of the track oi' F 1 on a smaller scale.showing the magnets applied to special conditions.

The letter A indicates the extreme lefthand end portion of a block ofrailroad track. and letters B, C, D, E. F, G, H, l, J and K indicatesubsequentbloclzs equipped with track magnets for the automatic controlof current traffic from left to right, as indicated by the arrowsappearing in block C, 1, and block F, 2. d i

The character A indicates a conventional wayside signal in the cautionposition at the end of block A; B a signal at danger at the endof blockB; C a signal at clear at the end of block C; D a signal at clear at theend of block D, which are operated re- 7 spectively through conventionalrelays, not

shown, by track circuits supplied by conventional batteries A B C and Dconnected respectively to the rails of blocks A, B, G and D, by wires A(the return wire A not being shown), B and B, C? and C", and D and D IWhile batteries and signals are not illustrated eXcep-t'as above, allblocks are assumed to be'provided with conventional batteries andsignals, or at least some form of conventional track circuit, which maybe utilized to control the track magnet relays which are of two types,quick action QB, QC and Q D, and slow action SB, SC, SD and SDX,respectively.

In the nomenclature used in this specifi cation and in the accompanyingdrawing, the letters, Q and S indicate a type of relay.

The letter Q, signifies a quick acting relay and the letter S a slowacting relay. When the letters Q or S are combined with a block letterB, C, or D, the location of a relay of a particular type. is indicatedby the block letter. The letter X indicates an extra relay of aparticular type. v

WVhere several similarly numbered members, or magnets indicated by theletter N appear and are combined with a black letter A to K, the blockletter indicates the block in which the numbered member or magnet N ispositioned; however, the block letter is omitted from the numerals inmost cases where the numbers first appear in block B.

The first quick actingrelay illustrated, of block B, indicated as QB,consists of a winding 10, surrounding an armature 11, upon which aremounted two contact bars 12 and 13. When the winding 10 is energized thearmature ll is lifted, as indicated in Fig. 1, which lifts contact bar12 out of contact with contacts 14 and 15 and breaks a circuit betweenthem; armature 11 in the indicated position holds contact bar 13 incontact with contacts 16 and 17, closing a circuit between them. Block Cis provided with a similar quick acting relay QC, shown in the downposition in'the drawing. Block D is provided with a similar relay QD,shown in the up position in the drawing, but its armature 11 islengthened downward to carry an extra contact bar 13, which makescontact with contacts 19 and 20 when armature 11 drops.

The lirst slow acting relay of block B, indicated as SB, consists of awinding surrounding an armature 31 which carries a contact bar 32,making contact with contact slides 33 and 34. In the indicatedupposition the winding 30 is energized. lVhen winding 30 becomesde-energized the armature 31 falls by gravity but at a slow rate,because of the conventional plunger 35 carried at the lower end ofarmature 31 and contained within theconventional stationary dash pot 36.The dash pot 36 may be so adjusted by varying the size of the escapehole 37 at the bottom of dash pot 36 that it will take, for instance, 90seconds for the armature 31 to fall far enough to break contact betweencontact slide 33, contact bar 32, and contact slide 34. A slightadditional tall causes the lower end 01 armature 31 to come to restabutting the lug 38 formed upon the bottom of the dash pct 36. Plunger35 is provided with a conventional inverted leather cup packing 39, sothat no dash pot action occurs when armature 31 is lifted by theenergization of winding 30. Block C is provided with a similar slowacting relay SC, and block D is provided with two similar relays SD andSDX.

findings 10 and 30 01 relays QB and SB are connected in parallel bywires 40 and 41 and from these wires respectively to the rails of blockB by wires 42 and a3. The windings 10 and 30 of relays QC and SC areconnected in parallel by wires 40 and 41 and from these wiresrespectively to the rails of block C by the wires 42 and L3 The windings10 30 and 3O of relays (all), SD and SDX are connected in parallel bythe wires 44- and L5, and 4:6 and ll", and from wires l4 and 45, to onerail of block D by wire 42, and from wires 46 and 47 to the other railby wire 43 Each block of track is provided with one or more trackmagnets NB, NC, etc, which form the primary of a split transformer, thesecondary being carried by rolling stock, as for instance shown in theabove mentioned application, Serial No. 517,391, and the control of thetrack magnets NB, NC, etc.,is the sole function of the above describedrelays.

The relays QB, QC, QD, SB, SC, SD and SDX may be emitted whenconventional wayside signal circuit relays, which may happen to bealready installed areprovided with available extra contacts as isoccasionally the case. In this event the extra con tacts may be calledupon to open and close the circuits of the magnets NB, NC, etc. in amanner similar to that described below with respect to the abovementioned relays which are controlled by the presence or absence ofrolling stock on a particular block and on the block ahead and by. thetime that rolling stock remains upon the block.

The track magnets NB, NC, etc. are energized periodically through therelays from a source of alternating current 50 through wires 51 and 52connected to wires 53 and 5% which parallel the track throughout itslength but are illustrated at blocks A, B, C, D and E only. Wires 53 and5% are tapped at intervals by other wires 55 55 55 and 55 and 60 6 D and60 which lead to contacts of the relays.

Rolling stock indicated by a pair of wheels W is shown at the middle ofblock C traveling in the direction of the arrow.

When wheels lV entered block C the rails were shortcircuitecl by them.therefore windings 10 and 30 of relays QC and SC which had been fed fromthe rails became (ls-energized, closing an alternating current circuitas follows: wire 53 wire 55 contact slide 341 contact bar 32,contactslide 33 wire 36 contact 15 contact bar 12 contact 14 wire 57 track nagnet NC, wire 58 track magnet N6 wire 59 and contact 16 of relay Q1),the arinature 11 of which is in the Lip-position, because norolling'steck is on block D. The circuit is continued from contact 16through contact bar 13,

falling. In the indicated position contact bar 32 has fallen halt-way,and should rolling stock indicated by the wheclslV be stopped on theblock (l, the circuit above described would be broken at contact slide34 contact bar 32 and contact slide 33 in, for instance seconds afterthe winding 30 had been tie-energized by the rails being short circuitedby wheels W and mag nets NC and NC would then become dead. The object ofthis arrangement of relay is to prevent rolling steer stopping at theend of for instance, block C and a following train entering block Cslowly against signals and then receiving a magnetic impulse from magnetNG,.Wl1lChYWO11ld resetits automatic. control device to clearasdescribed in the above mentioned application,

Serial-No.517,391

It should be noted that the circuit through track magnets'NC and .NCpasses through contact 16 contact bar 13 and contact 17 of relay QD, andthat if rolling stockhad been upon block D the circuit through trackmagnets NE and N13 is broken at contact 16 contact bar 13 and contact 17of relay QC, so that the track magnets of. block B cannot be energizedand made alive while rolling stock is on block C.

Block D is a block of extra length and for that reason it is notdesirable that the presence of rolling stock on block E should affectrolling stock entering block D, but

should only affect such rolling stock when it reaches the position ofbraking distance with respect to block E, therefore track nagnets ND andND are positioned with relation to the end of block D and not withrelation to its entrance. Blocks B and C are blocks of normal lengthwhich may be assumed to be about 1000 feet, which is usually consideredbraking distance.

hen rolling stock enters block D, armature 11 becomes de-energized anddrops from the indicated position and the rolling stock receives amagnetic impulse from the extra track magnet NDX through relay SDX viathe following alternating current circuit: wire 55, wire 70, contactslide 83,

contact bar 32 contact slide in, wire 71,

track magnet NDX, wire 72, contact 19, contact bar 18, contact 20, wire73, wire 60 and wire 54.

It will be observed that in general rolling stock on a block preventsthe track magnets on the block behind being made alive, and that shoulda train become stalled on any block the magnets after being energizedbecome dead in a predetermined interval of time, so as to prevent atrain creeping up from the block behind, receiving a track magnetimpulse as it enters an occupied block and so being permitted to advanceat full speed, in accordance with the operation of the device of thebefore mentioned application, Serial No. 517,391.

of railroads than collision of rolling stock, such as crossing busyhighways when the gates are up, going around a sharp curve at excessivespeed, running into an open switch at full speed, crossing a frailbridge, or a railroad crossing at high speed, running into anopen'drawbridge, etc., all of which,

and perhaps others, I aim to preventby breaking the track magnet circuit'when. a full stop of the rolling stock should be made, or. by omittinga track magnet where a train should be slowed down. 7 i

At theend of block E, Fig. 2, abusy highway 100 is shown crossing therailroadtrack and thetrack magnetcircuit-is completed in series with aswitch 101m wirei58 ,-carried by a gate 102 at-the crossing, so'thatwhen the gate102 is opened rolling stock receives no magnetic trackimpulse in block E and is automatically brought to a stop at the highway100. r

At the end of block F a sharp curve occurs at which a'train should slowdown, and the second magnet is omitted, as shown in the drawing. I

Block G is provided with a switch 110, and to avoid the entrance ofrolling stock into this switch without the train being first brought toa stop,one of the switch tongues 111 is provided with an insulatingbutton 112 which thrusts the electrical contact blade 113 out of contactwith the contact 114 and thus breaks the circuit through the trackmagnets NG and NG at wire 59 Block H crosses a bridge near its end andtherefore the first track magnet of this block is omitted, so thatrolling'stock approaches the bridge entrance at caution speed. i

The cross-over at the entrance to block J makes it necessary for thesecond magnet of block 1 to be omitted, so that speed will be reducedfor the cross-over.

Block K consists of a drawbridge rotatable degrees in the direction ofthe curved arrow 120 and to prevent a train running into it when it isopen, I mount a retaining bar 121, provided with an insulating button122, upon one of the tracks of the draw. Insulating button 122 holdsclosed a self-opening electrical switch 123, which opens in thedirect-ion of the curved arrow 124 when the draw opens in the directionof the arrow 120. Switch 123 is in circuit with wire 58 of block J, sothat the track magnets of block J become de-energized when the draw ofblock K is open and rolling stock is automatically stopped at the end ofblock J.

For the purposes ofthis application the feet from entrance of the block,second magnet 2200 feet from entrance of the block There are otherdangers in the operation and 1800 feet from the end of the block.

" This gives a normal intermagnet distance of 2000 feet. lVith thisspacing of the magnets a minimum of 5800 feet of unobstructed track willalways be found ahead of a live magnet.

I do not limit myself to the construction shown and the scope of myinvention is measured by my claims.

I claim:

1. A long block of track, a circuit normally unbridged by rolling stockbetween the rails and designed to be short circuited by rolling stockwhen the block is occupied, a relay connected across the rails designedto be de-energized by the short circuiting of the rails and to thenclose a track magnet circuit through a track magnet at the entrance ofthe long block irrespective of Whether the block ahead is clear oroccupied and to close a second track magnet circuit including a secondtrack magnet through a relay of the block aheadwhen the block ahead isunoccupied but not When. the block ahead is occupiec.

2; A block of track, a track circuit normally closed between'the railsand designed to be short circuited by rolling stock, a relay in thetrack circuit designed to be deenergized by the short circuiting of therails, close a track magnet circuit in the block, open a track magnetcircuit in the block behind and a delayed action relay in the trackcircuit designed to open the track magnet circuit after a predeterminedtime interval.

MEYER. D. MINNICK.

